Efficient synthesis of carbon‐14 labeled metabolites of the strobilurin fungicide mandestrobin using biomimetic iron‐porphyrin catalyzed oxidation

Abstract

Biomimetic oxidation using synthetic iron‐porphyrin (F20TPPFeCl) as a catalyst eliminated a xylene moiety of the fungicide mandestrobin, uniformly labeled with carbon‐14 at the benzyl ring, to produce the corresponding radiolabeled metabolite 1. This reaction mechanism was investigated by identifying chemical structures of intermediate 5 and p‐xyloquinone derivatives 6 and 7, as by‐products. Optimization of reaction factors based on the mechanism improved the yield of 1 from mandestrobin up to 87%. Finally, various carbon‐14 labeled metabolites of mandestrobin were prepared from 1.